. 
128 © The Philippine Journal of Science 1921 
In this laboratory it is customary to test one barrel of cement 
in every ten. Each sample of cement received by the Bureau 
of Science, so far as the Government is concerned at least, there- 
fore represents ten barrels of cement. Only one sample in every 
ten is tested for fineness, one in every five for time of setting 
and for specific gravity, but every sample is tested for sound- 
.ness and tensile strength. An incomplete chemical analysis is 
also made of every lot of cement received by the laboratory, 
a single composite sample being taken for this purpose. Table 
6 gives the loss on ignition, insoluble residue, sulphuric anhy- 
‘dride, and magnesia of some cements used in the Philippine 
Islands. 
TABLE 6.—Incomplete chemical analyses of Portland cement used in the 
Philippine Islands. 
Sulphuric 2 
Brand. aarti go oo a se ig 
Per eent.|Per cent.|Per cent.|Per cent. 
BONO Sous eer ae ea hee ta ie 1.63 0. 55 1,30 1.35 
CODA seas a ees ae ae ee eee 2.10 0. 25 Lit 2.12 
Cees ss oh Ss ae ee ee ee Sees 1.90 0.35 1.16 1.96 
Groen faland oo coe cca i wae abs be 1.85 0.44 1.25 1.95 
OTROS ocala cs ee 1.46 0.41 1.50 1.79 
Rigel ooo. 5S ae eae a esa ood a ee 2.73 0. 53 1.62 1.54 
In Table 7 are recorded the number of samples of Portland 
cement tested at the materials testing laboratory since the in- 
ception of such work in 1907 at the Bureau of Science. Pre- 
vious to that year the testing of Portland cement was scattered 
throughout the various government entities using it. 
Mineralogical composition.—Some of the sands were examined 
under the magnifying glass for the purpose of making a rough 
approximation to their mineralogical composition. In order 
TABLE 7.—Number of samples of Portland cement tested at the Bureau 
of Science. 
Year. Samples, Year, Samples. 
1907 re 24 1914 6,817 
1908 1,200 1915 6,716 
1909 *2,788 1916 ~ 15,790 
1910 "3,293 1917 5,687 
1911 *3,724° 1918 4,999 
1912 8,476 1919 6,888 
1913 9,535 
* Figures include a small unknown number of soil, fertilizer, and sand 
samples. 
‘ 
